It can be useful to monitor temperature or other properties at a variety of depths, such at different water or soil depths. Instruments exist that include a rod shaped body housing multiple temperature sensors. An example of such a device is the STP01, available from Hukseflux Thermal Sensors B.V. of Delfte, Netherlands. However, existing instruments typically suffer from various problems.
One such problem is the complicated wiring often associated with typical devices. Each sensor in a probe is typically individually wired. The resulting mass of wires is often difficult to work with and prone to tangling. Such problems can be magnified significantly when multiple probes are used. Increased wiring can also increase the chance of equipment malfunction. In addition, large amounts of wiring can increase the complexity and cost of the device, both material and manufacturing costs. In addition to increased cost, increased material use may make the devices larger in size. Larger sized devices may be less useful for some applications.
Large amounts of wiring can also increase the complexity of data analysis, as a particular measurement will involve analysis of a number of data streams. Multiple wires can also decrease the sensitivity of the device. For example, generally the more wire that is used, the greater the signal degradation caused by the resistance of the wire.
The SNAKU, sold by iButtonLink.com of East Troy, Wis., includes a plurality of analog thermocouple devices that are conveyed by individual wires encapsulated within a sheath to an interface circuit device located on one end. This circuit device performs a voltage measurement of the thermocouple output that is digitized and provides an address that permits identification and selected by a bus master on a 1-wire network. Thus, the SNAKU's use of analog sensors and associated cabling along its length can result in detrimental effects on data quality and application versatility due to size constraints.